Several different designs of methods, arrangements and constructions related to the technical field mentioned above including a current distribution circuit arrangement with an associated energy distributing DC-network for creating an energy supplied DC-network, by which the DC voltage level is held constant.
Direct current circuits shall not solely be designed so as to obtain a constant DC-voltage more or less independently of the load at that moment via an SP-unit and an after-coupled DC/DC-converter, but may also be adapted to compensate for occurring voltage variations, such as voltage dips or brief voltage shortfalls in the AC-network or DC-network distributing energy to the circuit arrangement.
One embodiment considered to lie close to known technology in this technical field is illustrated and described below with reference to FIG. 1 and FIG. 2, where an earlier known supply circuit or charging circuit is illustrated in a coupling technical fashion with an AC/DC-converter that includes a rectifying bridge, that includes four full-wave-rectifying diodes or diode assemblies, an SP-unit, a DC/AC-converter, a circuit isolating transformer, and an AC/DC-converter for supplying a DC-network to which energy shall be distributed.
FIG. 1 is intended to describe briefly two or more parallel related energy distributing DC-networks of mutually the same type, having associated energy or power distributing circuit arrangements.
FIG. 2 illustrates in more detail the coupling, technical construction of each of the separately supplied circuit arrangements shown in FIG. 1, from which it will be seen that the parallel coupling, illustrated in FIG. 1, is comprised of an electrically isolated circuit arrangement via the transformer couplings used.
In respect of an energy distributing AC-network (or DC-network) to a known circuit arrangement of the construction shown in FIG. 2 it is known that the creation of an energy-supplied DC-network, with a DC-voltage that is kept constant, suffers different drawbacks and challenges, dependent on different circumstances.
A first drawback or challenge in respect of prior art circuit arrangements is that in order to function satisfactorily they require a large number of components, among other things in the form of program controlled transistors which shall create within the circuit arrangement from a created DC-voltage zero transits for an internally generated AC-current or an AC-voltage that can be coupled alternately to a requisite transformer and after-coupled rectifying units for forming a DC-network, and those skilled in this particular art have a pronounced need to be able to create the same functions with the hope of being able to utilize far fewer components with lower circuit-internal power losses.
Another drawback or challenge is concerned with the ability to maintain a voltage-constant energy-supplied DC-network to a connected customer circuit, even when the energy distributing AC-network (or DC-network) is subjected to profound voltage dips, voltage increases and/or short-term breakdowns.
A third drawback or challenge resides in the ability to couple a plurality of energy supplied DC-networks in parallel and to utilize in this parallel coupling one and the same electric conductor, that shall be related to a common point or reference point.
The present invention provides primarily means for solving this third challenge.
The contents of the patent publications listed below do belong to the earlier standpoints of techniques:    EP-A1-0170932,    US-A1-2005/0 052 165,    EP-A1-1 381 135, and    EP-A2-0 582 183
Patent publication EP-A1-0 170 932 illustrates and describes a coupling arrangement for distributing rectified electric energy to one or more consumers and can be considered to teach the basic conditions of the present invention in this regard.
The patent publication thus teaches a series coupling of an SP-unit and a DC/DC-converter.
FIG. 3 of said patent publication clarifies the use of a voltage (340 V), that can be adjusted to a fixed state, and a voltage converter (8).
The voltage converter (8) is illustrated in FIG. 3 as a transformer (82) that has separate and therewith electrically isolated primary and secondary windings, where the primary winding is controlled by a field effect transistor (81) and conforms to the technique illustrated and described with reference to the coupling arrangements according to FIG. 2 of the present application.
Patent publication US-A1-2005/0 052 165 illustrates and describes an arrangement for creating distribution of converted electric energy to a load, where said conversion is based on a DC-converter, and where measures have been taken to optimize its efficiency.
There is described to this end the use of an impedance in a voltage converting or voltage transforming circuit.
FIG. 5 of said patent publication also clarifies that a conductor extending through the circuit includes a series-connected inductance (1-8), wherewith such a coupling would completely jeopardize and, in practice, make the parallel related coupling significant to the present invention totally impossible to achieve.
Patent publication EP-A1-1 381 135 describes a battery powered electronic circuit arrangement and is intended to compensate and control a voltage level when an output voltage from a battery (201) lies beneath the voltage level required for coupling a load to the circuit arrangement. This publication relates to a coupling arrangement that enables voltage to be increased or lowered.
Finally, patent publication EP-A2-0 582813 illustrates and describes a coupling arrangement which is constructed to afford high power factors and a low harmonic distortion, with the aid of FET-transistors and/or MOSFET-transistors and with an electrically insulated or isolated DC/DC-converter in respect of load connected to the coupling arrangement.